A brief and sketchy history of Tenjiku Shogi. Some form of Shogi was probably being played in Japan before 1027 when it was first mentioned. From there the game evolved into many larger forms of Shogi and these games had pieces with ever more exotic moves. Chu Shogi was first mentioned in a text dating around 1350 and was the most popular form of Shogi then and popular with noblemen and high-ranking monks. During the 16th century a small variant played on a 9x9 board (Sho Shogi) introduced the drop rule, giving us the modern game of Shogi. Although Shogi with drops became very popular most variants, being too large, were played without drops. Tenjiku Shogi, often called "Exotic Shogi", was derived from Chu Shogi and was possibly invented by Buddhist monks in the 16th century. More than mere evolution, a lot of effort seems to have gone into the game play and design. Once played it becomes clear that the major pieces are all set up in just the right place for attack and defence, it is a well thought out game. At the end of the 16th century it was recorded that Minase Kanenari and his sons produced sets for Sho Shogi, Chu, Dai, Dai-Dai, Maka-Dai-Dai and even four for Tai Shogi. But there was no mention of any Tenjiku Shogi sets, was the game unknown then. The rules of Tenjiku Shogi were first given in a book called "Shogi Zushiki", published in 1634. (Tenjiku was the Japanese name for India which was considered an "exotic" land in the 16th century). Modern Tenjiku Shogi and recent history. The Shogi Association produced Tenjiku set and rule leaflets in the early 1980's. The Shogi Variants program is mainly based on the rules leaflets, Version 1.0 was released in January 1996. "Tenjiku Shogi - The Struggle for Survival" was published in Portable Document Format by Colin Adams prior to 2000. Two supplements were added and the following footnote. "After experimenting with the critical line in the second supplement, I believe that it is not viable, and that the game is a win for the first player". Sadly much effort was lost on the excellent works above. Other web sites with Tenjiku content also followed these rules. It is not that all sites are in agreement with the rules, it is simply the they all followed the first. Towards the end of 2000 Edi Werner proposed his changes to the Jumping Generals capturing rule. September 2000, Colin, in a "ShogiVar" message, agreed that the new rules seemed to give equality but needed testing. Richard's PBeM server for Tenjiku was set up with the new rules sometime before 2005 . Lucky Dog Tenjiku pages started July 2005 Wikipedia Tenjiku page started September 2005 The last three internet sites all promote the same rules and these are used by current players.

A look at the old Tenjiku rules and why they were changed.

Colin sent me this (11 Aug 2005) as a proven win;
1.P-8k P-8f 2.GGn-3g VGn-6f 3.GGnx7c GGnx7c 4.RGnx7e+
But that wasn't the line that convinced me it was a dead game, I remember it was on the left side of the board.

So after a little look, let's see how the above line works;
1.P-8k P-8f 2.GGn-3g VGn-6f [a] 3.GGnx7c GGnx7c [b] 4.RGnx7e+ [c]
[a] I'm not sure what the VG is doing here bar forcing the GG to do what it intends to do. Other VG moves are worse..
2.--- VG-7f 3.VG-6k or similar and the white Fi is still en prise but the black RG no longer needs to take the pawn as the black Fi is free to move. (VG-7f was to prevent RGx7e+.
2.--- VG-3j 3.GGx3j and if the Fi retakes the GG then either the BG or VG will take the Fi.
[b] Attacks the 'trapped' Fi. Nothing else to consider in this position.
[c] What this does is to promote the RG to a GG preventing the white GG jumping to capture the Fi. It also allows the black Fi to move away when it is attacked. At this point black is Fi for GG & RG up.

Here's a quick look at another counter attack and a defence;
1.P-8k P-9f 2.GG-3g GG-14j 3.GGx7c GGx10n 4.GGx10c GGx7n 5.GGx9b DEx9b 6.FKx7n
Black is a FK up with no Fi's on board and just needs to keep exchanging down to make the advantage tell.

1.P-8k SE-3f 2.GGn-7k Wins the Fi

Under these old rules the jumping generals can never give check nor attack an equal ranking piece by jumping. This leaves the jumping generals with only a little more power than their non jumping counterparts. The Fi's seem even more valuable than they are in Tenjiku (New Tenjiku).

Please do NOT use the old rules - it can only serve to injure the game, there are enough Shogi variants without variants within variants!

There may be errors, so anyone who wants to take a deeper look at these lines please do. You can post any errors or improvement here.